''Quercus greggi'', otherwise known as the Mexican oak, is a

monoecious Monoecy (; adj. monoecious ) is a sexual system in seed plants where separate male and female cones or flowers are present on the same plant. It is a monomorphic sexual system alongside gynomonoecy, andromonoecy and trimonoecy. Monoecy is conne ...

semi-evergreen Semi-deciduous or semi-evergreen is a botanical term which refers to plants that lose their foliage for a very short period, when old leaves fall off and new foliage growth is starting. This phenomenon occurs in tropical and sub-tropical woody spe ...

oak that is adapted to survive in arid conditions. It is native to Mexico and commonly grow around north of the 24th parallel and spreads across multiple locales. The plants grow to approximately in height (can be as small as ) and in width with waxy rounded-ovular

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

that have dimensions of around 3–6 x 2–4 centimetres. The leaves are generally covered in a dense layer of

trichome Trichomes (); ) are fine outgrowths or appendages on plants, algae, lichens, and certain protists. They are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae. A covering of any kind of hair on a pla ...

s. The bark is scale-like and light gray; it is covered in small lenticels, allowing the plants to undergo gas exchange with the surrounding atmosphere. The twigs of the plant are covered in thick woolly hairs. Around April, the trees produce

catkin A catkin or ament is a slim, cylindrical flower cluster (a spike), with inconspicuous or no petals, usually wind-pollinated (anemophilous) but sometimes insect-pollinated (as in ''Salix''). They contain many, usually unisexual flowers, arranged cl ...

s that can have approximately 18 flowers are around 3–4.5 cm long. As the plants are monoecious (producing male and female cones on the same plant), they also produce female

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

s. The female inflorescence generally grow around 2–4 flowers and are covered in trichomes, like the leaves of the plants. Like many more commonly known oaks, Mexican oaks utilize their male and female reproductive structures to produce the acorn nuts of the plant, which can appear alone or in clusters on small peduncles stemming from the main branches. The acorns contain a seed and eventually fall from the tree to start the growth of a new Mexican oak. La Siberia is a cultivar of this species.

References

* {{Taxonbar, from=Q11944220 greggii Endemic oaks of Mexico Flora of the Sierra Madre Oriental Flora of the Sierra Madre de Oaxaca